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A new method to prepare p-type CdS thin film was investigated, in which the laser ablation was applied to a mixed target of CdS and Cu. The p-type CdS film was obtained from a target containing more than 5 at% Cu. Composition analysis showed that Cu content in the film was about one-fifth of that in target. The formation of p-type CdS film was also confirmed by the photovoltaic effect of the p-n junction which was constructed by laminating n-type CdS film and p-type CdS film.

Pure and several Cu2O-doped binary lithium borate glasses have been prepared and annealed. Extensive measurements of the temperature-dependence of DC electrical conductivity were made on these samples and the corresponding activation energies of conduction were evaluated in each case. The results obtained are discussed in detail. They indicate that the phenomena of the formation of BO3 triangles and a mixed alkali metal effect appear.

The dynamic shift of EPR absorption line which originates from the low-symmetric spacial distribution of spins has been measured in the impure one-dimensional Heisenberg system (CH 3 ) 4 NMn 1- x Cu x Cl 3 (TMMC: Cu) with x up to 0.045 at both 9.45 GHz and 23.65 GHz. The observed shift is enhanced in its amount when Cu concentration x is increased, whereas the angular-behavior is similar to the case of pure TMMC. These results can be explained by the reduction of decay-rate of spin correlation function. Analysis of the experimental data on the basis of the diffusion model of impure chain reconfirms the validity of the theory of dynamic effect of low-symmetric spin-arrangement which has been previously proposed by present authors.

PL and PLE spectra of a-Ge 0.15 Se 0.85 samples doped with up to 1 at. % In, Cu and Fe are measured from 4 K - 150 K. The insensitivity of all aspects of PL (including fatigue) to In and Cu doping is noted. Fe doping significantly quenches PL and PLE spectra, and a slight modification of the PL temperature dependence is observed. An increase in the efficiency of non-radiative recombination through a structured impurity mechanism is proposed for Fe. Specific defect structures consistent with PL and PA measurements are suggested with preferred inclusion of Fe 2+ at a Ge site.

Lead sulphide thin films have been deposited by conventional chemical bath technique. The effect of Cu doping is studied on the resistivity and the band gap of these films. An anamolous behavior is obtained in the case of variation of band gap with impurity (mol%) which shows that certain values of impurity have prominent features. While the resistivity decreases first with the increase in impurity, after a particular value the resistivity adopts a rising trend, and on still higher doping the decreased resistivity again starts to take place.

Using Au 198 und Ag 110m as tracers the diffusion of gold and silver is measured in bulk samples of glassy As2Se3. In doped arsenic selenide the temperature dependence of the diffusion coefficient D obeys the following Arrhenius equations: DAg = 3 exp (−0.89 eV/kT) cm2/s; DAu = 6 exp (−1.15 eV/kT) cm2/s. Doping with Ge remains DAu and DAg unchanged, Cu doping markedly decreases the diffusion. The results are discussed with respect to the diffusion mechanism. Unter Verwendung von Au 198 und Ag 110m als Tracer wird die Diffusion von Gold und Silber in kompakten, glasartigen As2Se3-Proben gemessen. In undotiertem Arsenselenid last sich der Diffusionskoeffizient D durch folgende Arrhenius-Beziehungen darstellen: DAg = 3 exp (−0,89 eV/kT) cm2/s; DAu = 6 exp (−1,15 eV/kT) cm2/s. Durch Ge-Dotierung bleiben DAu und DAg unverandert, durch Cu-Dotierung werden sie deutlich vermindert. Die Ergebnisse werden im Hinblick auf den Diffusionsmechanismus diskutiert.

Cu-doping effects in CdI2nanocrystals are studied experimentally. We use the photostimulated second harmonic generation (PSSHG) as a tool to investigate the effects. It is found that the PSSHG increases with increasing Cu content up to 0.6% and then decreases due to the formation of the Cu-agglomerates. The PSSHG for the crystal with Cu content higher than 1% reduces to that for the undoped CdI2crystal. The results suggest that a crucial role of the Cu-metallic agglomerates is involved in the processes as responsible for the observed effects.

Experimental results obtained using a CdS/CdTe/ZnTe top cell on a CdS/CuInSe/sub 2/ bottom cell are presented. Single cells of each type exhibit an 11% efficiency. The fabrication of a mechanically stacked CdTe-CuInSe/sub 2/ tandem cell that shows an efficiency of 9.9% is discussed. The current of the CuInSe/sub 2/ cell is limited by the transmission through the CdTe cell. Semiquantitative analysis of the optical losses in the structure indicates that substantial improvements in tandem device performance can be achieved by: reducing free carrier absorption in the transparent (SnO/sub x/) top contact, e.g. by using an alternative transparent contact such as ITO or ZnO which has better near-IR transmission, and reducing the absorption in the Cu-doped ZnTe layer-perhaps by reducing the Cu doping level. >

An investigation of photoconduction (PC) in bulk doped and undoped Ge y Se1-y glasses (y≤0.4) is reported between 1.2 eV and 2.8 eV between 50 K and 390 K. PC is predominantly by holes, even for 0.4≥y≥0.15 material, with a typical activation energy 0.20 eV. PC is increased significantly for low (0.1–1 at.%) In doping, and reduced for Fe and Cu doping. These changes, together with observed changes in dark currents and activation energies, are modelled in terms of gap-state impurity distributions. Persistent PC is observed which depends strongly on y but is doping independent. A model to explain this is outlined.